Electric billet heating machine



April 18, 1950 K. F. BARLOW 2,504,790

ELECTRIC BILLET HEATING MACHINE Filed Nov. 6, 1946 2 Sheets-Sheet 1 WITNESSES: lNVENTOR M. Ken/7929; {Bar/0144 end face, and local overheating results.

Patented Apr. lg, 1950 ELECTRIC BILLET HEATING MACHINE Kenneth Frederick Barlow, Preston, England, assignor to The English Electric Company Limited, London, England Application November 6, 1946, Serial No. 708,078 In Great Britain November 7, 1945 Claims.

I f This invention relates to electric billet heating 3 machines of the type in which a billet is gripped between opposed electrodes and heated by passing current therethrough.

, In such machines it is important, in order to ensure even heating of the billet, that the ends In practice, however, it frequently happens that one or both ends of the billet are not cut off square, with the result that contact is only made between each electrode and one part of the billet One object of the present invention is to overcome 'this disadvantage and provide electrodes which make good contact with the billet over substan- ;tially the whole of their contact surfaces.

According to one feature of the invention, an electric billet heating machine comprises, in

combination, opposed electrodes, means for moving at least one of said electrodes towards the other electrode to grip a billet therebetween, and

means for connecting said electrodes to a source of supply for heating the billet, at least one of said electrodes being tiltably mounted so as to allow said electrode automatically to align with the end face of the billet.

Thus if the ends of the billets are not cut' square, at least one of the electrodes will auto- -matically align itself with the end of the billet to ensure a good contact over substantially the whole contact surface of the electrode.

A preferred method of carrying out the invention is illustrated in the accompanying draw- For purposes of at an angle relative to the plane normal to the axis of the billet, whilst the electrodes are shown in the position at which self-aligning is about to occur.

Referring now to the drawings, two axially op- .posed electrodes I and 2, screwed into holders 3 and 4 respectively, are adapted to grip a billet 5 between their contact faces Ia and 2a when pressure is applied to a ram 6 slidable in the .hydraulic cylinder 1.

The holder 3 is resiliently attached to a back- ,ing plate 8 carried on the machine frame 9, whilst the holder 4 is resiliently attached to a backing plate I0 carried on the ram 6. Resilience is obtained by a number of circumferentially disposed to .and 2a.

relative to the backing plate 8 when the springs Ila are compressed causes the lever 26 to engage helical compression springs II and Ila and each holder 3, 4 is attached to the corresponding backing plate by studs I2 passing through relatively large clearance holes I3 in the two backing plates. Nuts Id having conical surfaces I4a engaging corresponding surfaces in the backing plates 8 and I0 respectively limit the axial clearance space between the holders and the backing plates.

The electrode I has formed therein a groove I b around which cooling fluid from an inlet pipe I5 is circulated and subsequently exhausted through an outlet pipe IS. A similar groove 2b is provided in the electrode 2 around which cooling fluid from the inlet pipe I8 is circulated and subsequently exhausted through the output pipe I9. Flexible connections 20 and 2| connect the electrodes I and 2 to the backing plates 8 and I0 respectively.

Mounted on the backing plate 8 is a push but-- ton type switch 22, the push button of which is; shown at 23, controlling a relay 24 in the circuit,

between the source of supply 25 and the elec-- trodes. The push button is actuated by a lever 26 pivoted on an axially adjustable sleeve 27 and With the holder 3 in the; position shown, the switch is in the open circuit condition and the lever 26 engages a stop 3| on the switch 22. A further step 32 is also provided the function of which will be described later.

In operation the billet 5 is placed between the electrodes I and 2 and pressure applied to the 'ram 6 whereby the electrode 2 1S moved upwards and the billet gripped between the contact sure faces Ia: and 2a of the electrodes. The pressure,

applied to the ram 6 is just sufficient partially to, .compress the springs I I and I Ia, and the holders 3 and 4, being free to tilt in any horizontal posi tion, correctly align themselves so that the electrodes contact the ends of the billet over substantially the whole of their contact surfaces I a. The axial movement of the holder 3' the push button 23 whereby to close the switch '22, which thus energizes the relay 24 to complete the supply to the electrodes I and 2.

If for any reason an excessive pressure is ap-- -'plied to the billet, causing the springs I I and I la to compress beyond their normal working range,

the resulting further upward movement of theholder 3 causes the lever 26 to engage the stop.

'means for mounting at least one of said holders 32 which now acts as a fulcrum for the lever. The part of the lever engaging the push button 23 now moves in the opposite direction to disengage the push button whereby the switch 22 opens its contacts and the relay 24 breaks the power supply to the electrodes I and 2. The pressures at which the switch operates may be varied by adjustment of the position of the sleeve 21 on the stud 29. Until the excess pressure is removed, the circuit to the electrodes cannot again be completed.

What I claim as my invention anddesire to secure by Letters Patent is:

1. An electric billet heating machine comprising in combination, two machine members at least one of which is provided with a plurality of spaced axial openin s, means operable to effect relative movement of said machine members toward and away from each other, an electrode holder on each machine member, opposed electrodes in said holders disposed to grip a billet therebetween, .a plurality of stud members attached to one of said holders and extending through the spaced axial openings inthe said one machine member for connecting one of said holdem vto its associated machine member, said stud gmembers being of smaller diameter than the openings in the machine member having ad- .justable nuts on their free ends to adjust and limit the maximum axial spacing between the holder and-machine member, and a plurality of spring members interposed between the said one holder and its associated machine member for .normallybiasing the holder away from the machine member, whereby the holder is mounted on 'its associated machine member for both axial and tiltingmovement relative thereto.

2. An electric billet heating machine comprising, in combination, two machine members, an electrode holder mounted on each machine mem-, ber, opposed electrodes in said holders, means for efiecting relative movement of said holders towards and away from each other to grip abillet between said electrodes, means for connecting said electrodes to a source of electrical energy for heating thebillet, means for mounting at least one of said holders on its associated machine member comprising a plurality of studs extending axially from said one holder through relatively large clearance holes in said machine member, stop members on the ends of the studs to limit the separation of said one holder and said member, and at least one compression spring interposed between said one holder and said member tending to maintain a predetermined axial clearance space between said one holder and said .member by biasing them apart to a distance determined by the stop members.

3. An electric billet heating machine comprising, in combination, two machine members, an electrode holder on each member, opposed electrodes in said holders, means for eifecting relative movement of said holders towards and away from each other to grip a billet between said electrodes,

on its associated machine member comprising a plurality of studs extending axially from said one holder through relatively large clearance holes .in said machine member, stop members on the ends of the studs to limit the separation of said holder and said machine member, at least one compression spring interposed between said one ,holder and said machine member tending to -.maintain a predetermined axial clearance space between said one holder and said machine memcomprising a plurality of studs extending axially from said one holder through relatively large clearance holes in said machine member, stop 1 members on the-ends of said studs to limit the separation of said one holder and said machine member, at least one compression spring interposed between said one holder and said machine member tending to maintain a predetermined axial clearance space between said one holder and said machine member, and switchingmeans actuated by movement of said one holder relative to said machine member so as to complete a cir- 'cuit from said electrodes'to a source of supply for heating the billet with a predetermined axial movementof said one holder towards said machine member and to break said circuit with a predetermined further axial movement of said one holder towards said machine member.

5. An electric billet heating machine comprising, two machine members, an electrode holder individual to each machine member, means including a plurality of stud members connecting each holder to itsassociated machine member for a predetermined amount of axial and tilting movement relative thereto, opposed electrodes mounted on the-holders, a plurality of compression springs interposed between each holder and its associated machine member for normally biasing said-holders and members apart, said connecting studs and said springs permitting said holders to move axially and tilt in any direction relative to their associated machine members, and means for moving at least one of said machine members toward the other to grip a billet between the electrodes.

6. An electric billet heating machine comprising, two machine members, an electrode holder ,mounted on each machine'member, means including a plurality of stud members loosely connecting at least one of said holders with its associated machine member for a predetermined amount of axial and tilting movement with respect thereto; a plurality of spring members interposed between said holder and said machine member biasing them apart, flexible current conductors interconnecting said loosely connected holder to its associated machine member, opposed electrodes in said holders, means for moving at .least one of said machine members toward the other to grip 9, billet between the electrodes, and switch means disposed to be actuated in accordance with the axial movement of said loosely connected holder with respect to its associated machine member for controlling the supply of electric current to the electrodes.

7. An electric heating machine for heating billets and the like comprising, a frame, a first back plate mounted on the frame, said back plate having a plurality 01' recesses in one face thereof,

' a second back plate, actuating means mounted on the frame for supporting the second back plate --in-spaced relation with the first back plate and moving it toward and away therefrom, a first electrode holder mounted on the movable back plate, a second electrode holder, said holder having a plurality of recesses in one face thereof, means including a plurality of stud members securing said second holder to the first back plate for a predetermined amount of axial and tilting movement relative thereto with their recessed faces together, a plurality of tension springs interposed between said holder and its back plate with their ends seated 1n said recesses normally biasing the holder to its maximum outward position therefrom, flexible current conductors interconnecting said electrode holder and its back plate, and opposed electrodes mounted in said holders for gripping a billet therebetween when the movable back plate is actuated toward the fixed back plate.

8. An electric heating machine for billets and the like comprising, a frame, a hydraulic ram mounted on the frame, a first back plate having a relatively fiat-face portion with recesses therein fixedly mounted on the frame opposite and in spaced relation to the ram, a second back plate also having a relatively fiat-face portion with recesses therein mounted on the ram to be moved thereby toward and away from the first back plate, a first electrode holder having a relatively fiat-face portion with recesses therein mounted on the second back plate, a second electrode holder also having a relatively fiat face portion with recesses therein mounted on the first back plate, said holders and back plates having their face portions together, stud members loosely securing the holders and back plates together for relatively axial and tilting movement, spring members positioned between the holders and back plates with their ends disposed in said recesses, and opposed electrodes mounted on said holders for gripping a billet when the second back plate and its associated holder are actuated by the ram.

9. An electric heating machine for billets and the like comprising, a frame, a hydraulic ram mounted on the frame, a first back plate fixedly mounted on the frame opposite and in spaced relation to the ram, a second back plate mounted on the ram to be moved thereby toward and away from th first back plate, a first electrode holder means including a, plurality of stud members loosely securing said holder on the second back plate, a second electrode holder, means including a plurality of stud members loosely securing said holder on the first back plate, a plurality of springs disposed between each holder and its back plate to provide both axial and tilting movement therebetween, and opposed electrodes mounted on said holder for gripping a billet therebetween when the holders are moved together by the ram.

10. An electric heating machine for billets and the like comprising, a frame, a hydraulic ram mounted on the frame, a first back plate fixedly mounted on the frame opposite and in spaced relation to the ram, a second back plate mounted on the ram to be moved thereby toward and away from the first back plate, a first electrode holder mounted on the second back plate, a second elec trode holder mounted on the first back plate, said holders being mechanically secured to their associated back plates for both axial and tilting movement relative thereto, a plurality of spring members positioned between said holders and their back plates normally urging said holders and back plates apart, opposed electrodes mounted on said holder for gripping a billet therebetween when the holders are moved together by the ram, and switch means having open and closed positions disposed to be actuated to the closed position in response to a predetermined amount of relative movement between one of the electrode holders and its backing plate for controlling the supply of current to the electrodes.

KENNETH FREDERICK BARLOW.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,434,374 De Lemon et a1 Nov. 7, 1922 2,151,342 Von I-Ienke Mar. 21, 1939 2,266,424 Humphrey Dec. 16, 1941 2,330,658 Albright Sept. 28, 1943 2,346,088 Shobert Apr. 4, 1944 2,348,884 Dewees May 16, 1944 2,369,240 Kirby Feb. 13, 1945 2,405,033 Grimes July 30, 1946 FOREIGN PATENTS Number Country Date 476,872 Great Britain Dec. 13, 1937 

